Elevator.



PATENTED OCT. 11, 1904.

- H. R. WELLMAN.

ELEVATOR.

' APPLICATION PILED'NOV. 25, 1902.

N0 MODEL.

FIGZ.

Fl GB.

WITNESSES 2 INVENTOR 7%) M M v ZTTORNEY UNITED STATES Patented. October 11, 1904.

PATENT OFFICE.

HAROLD ROBINSON WELLMAN, OF NEW YORK, N. Y., ASSIGNOR OF ONE- THIRD TO EDWARD S. ISHAM, OF NEW YORK, N. Y.

ELEVATOR- SPECIFICATION forming part of Letters Patent No. 772,074, dated October 11, 1904.

Application filed November 25, 1902. Serial No. 132,837- (No model.)

To all whom, it may concern.-

Be it known that I, HAROLD ROBINSON WELLMAN, a citizen of the United States, residing at New York city, county and State of New York, have invented certain new and useful Improvements in Elevators, of which the following is a specification.

My invention relates to elevators of the type now known as endless-rope elevators.

My invention consists in certain features of construction, which will hereinafter be described and claimed. v

The practical idea involved in this invention is found in the fact that if a rope is carried over two driving-sheaves of the same diameter rotated at the same speed the linear velocity of the rope at the driving-sheaves will be the same, and if the diameters of the sheaves are altered as regards each other- 2'. a, if either one is made larger or smaller than the other-the linear velocity of the rope at the respective driving-sheaves will be correspondingly altered. v

The object of my invention is generally to improve the construction and to decrease the cost of operation of elevators.

The accompanying drawings will serve to illustrate my invention.

Figure 1 is a side elevation showing the general arrangement of parts where a sheave of fixed diameter and a sheave of variable diameter are used and the mechanical means for varying the diameter of the variable sheave. Fig. 2 is a view in perspective of one form of sheave of variable diameter provided with a rotatable guide having parallel grooves on its surface inclined to the left. Fig. 3 is a view in perspective of a rotatable guide with parallel grooves on its surface at right angles to the axle of the guide. Fig. 1

is a similar view with parallel grooves inclined to the right. I

Similar numerals indicate like parts.

In the drawings, 5 indicates an elevator-car; 6, motor, which may be of any kind, preferably an electromotor; 7 endless rope; 8, pulleys which occupy a fixed position at the top of the elevator-shaft; 9, pulley connected to the top of the elevator-car; 10, pulley fas tened to one end of a rope 11, which passes over pulley 12 at the top of the elevatorshaft and is connected at its lower end to a counterweight 13. The motor 6 is connected through suitable gears 14 14 to a shaft 15, mounted in bearings 16. Located on and secured to the shaft 15, Fig. 1, at one end is a sheave 17 of fixed diameter and on the other end a sheave 18 of variable diameter. The sheave 18 is shown as cone-shaped and provided with a rotatable guide 19, secured to a shaft 20, which is mounted in suitable bearings 20 on the sheave 18. Formed in the surface of the sheave 18 are the parallel grooves 21. The rotatable guide 19 has three convex faces 22 23 24, and formed in these faces are grooves differently disposed for each face. The face 22 has a series of parallel grooves 25 inclined to the left and one groove 25 at right angles to the axis of the guide. The face 23 has a series of parallel grooves 26, all of which are at right angles to the axis of the guide. The face 24: has a series of parallel grooves 27 inclined to the right and one parallel groove 2.7 at right angles to the axis of the guide.

The object'of the grooves on the faces of the rotatable guide is when the rotatable guide has, for instance,its effective face in the position shown in Fig. 2 to gradually shift the rope from groove to groove toward the larger diameter of the sheave, or when the rotatable guide has, for instance, its effective face in the position shown in Fig. 3 to maintain the rope in one groove on the sheave of variable diameter, or when the rotatable guide has its effective face in the position shown in Fig. 4: to shift the rope from the large toward the small diameter of the sheave. The object of the groove 25 on the face 22 and the groove 27 a on the face 24 is to stop the movement of the rope when it has reached its limit of travel on the sheave of variable diameter. A further purpose. of the groove is by presenting an extended bearing-surface for the rope 7 to increase the frictional resistance between the rope and the sheave 18.

For varying the effective diameter of the sheave 18 any suitable means may be employed. The means shown consists of an endless rope 33, passing over pulleys 34 35, located, respectively, at the top and bottom of the elevator-shaft. Secured to the pulley 35 is a forked arm 36, on the forward ends of which are inwardly-projecting pins 37, which are located in a slot 38 in the periphery of a sleeve 39, splined on shaft 15, which sleeve is adapted to be rotated by and to be moved longitudinallyalongsuchshaft. Dependingfrom oneend of the sleeve 39 is a projection 40, which is situated in a cam-slot 11 in sleeve 42, mounted on the left-hand end of shaft 20, on which the rotatable guide 19 is mounted. By making traction upon or lifting the rope 33 the arm 36 on the pulley 35 is caused to be moved to the right or left, as desired, thereby moving the sleeve 39 correspondingly, which acting through the cam-slot 4:1 in the sleeve 42 on shaft 20 serves to rotate the guide 19 to some one of its three positions as desired.

When the parts are in the position shown in Fig. 2, with the grooves in the guide 19 inclined to the left, the endless rope 7 will be directed along the sheave toward its greatest diameter, and hence the effective diameter of the sheave will be increased. hen the rotatable guide occupies the position shown in Fig. &t'. a, with the grooves in the guide inclined to the rightthe reverse will be the case. When the grooves in the guide are coincident with those on the sheave, as shown in Fig. 3, the rope will occupy a single groove on sheave and guide and will not change its position.

I do not limit myself to the specific mechanism shown for altering the effective diameter of the sheave 18 or for rotating the guide 19, as other mechanism may be employed to accomplish the same result.

The operation of my device is as follows: Assuming the linear velocity of the sheaves 17 18 at any moment to be the same, no motion up or down of the elevator-car will take' place and the endless rope will be fed from one sheave to the other at exactly the same speed. If, now, the effective diameter of the sheave 18 be increased relative to 17 and assuming the rope to be moving in the direction indicated by the arrows, the rope will be taken up by the sheave 18 faster than it is fed from the sheave 17, and consequently the elevatorcar will rise. Conversely, if the effective diameter of the sheave 18 is decreased relatively to that of the sheave 17 the rope will be fed faster from the sheave 17 than it is taken up by the sheave 18 and the elevator-car will descend.

It will be observed that in the construction where one sheave is of fixed diameter and the other of variable diameter means must be provided to compensate for the strain which would otherwise be put upon the rope in moving toward the large diameter of the sheave.

Such a means is found in the pulley 10 and the compensating weight 13, which permits of vertical movement of the pulley corresponding to change of position of rope upon the variable sheave.

It will be understood that by reason of the construction described and with a constantlydriven motor the load in starting will be gradually thrown upon the motor and, further, that as the car ascends a gradually-varying leverage is brought into operation to overcome the load. This feature of variable and gradual application of leverage will be understood from the followingconsiderations: Assuming the shaft 15 to make one hundred revolutions a minute and the effective circumference of the sheave 17 to be five feet and that of the sheave 18 as six feet, then the peripheral speeds of the sheaves 17 and 18 will be, respectively, five hundred and six hundred feet a minute and the car will be raised at the rate of fifty feet a minute. Assuming now that the effective circumference of the sheave 18 is one-tenth of a foot greater instead of one foot greater than the effective circumference of the sheave .17, it will be at once seen that the leverage will be increased ten times, or where the effective circumference of the sheave 18 is one-hundredth of a foot greater than that of sheave 17 the effective leverage is onehundred times greater. It will be observed from the above considerations that the starting-current of the motor can be kept down and, further, that when heavy loads are to be lifted any load within the breaking limit of the system may be lifted at a speed inversely proportional to the weight to be lifted.

Having thus described my invention, I claim 1. An elevator comprising in its construction, a car, a driven shaft, an endless rope connected through pulleys to the car, sheaves on said shaft, one of fixed diameter and one of variable effective diameter, said sheave with the variable effective diameter comprising a cone having grooves on the face thereof, and a rotatable guide having a series of faces with the grooves differently disposed on said faces, and means for changing the acting faces of said rotatable guide.

2. An elevator comprising in its construction, a car, a driven shaft, an endless rope connected through pulleys to the car, sheaves on said driven shaft, one of fixed diameter and one cone-shaped with grooves thereon, and means for causing said endless rope to be gradually moved over the surface and into successive grooves on the cone-shaped sheave.

IIO

tion, a car, a driven shaft, an endless rope may be caused to move through successive connected through pulleys to the car, sheaves grooves on said cone.

on said shaft, one of fixed diameter and the In testimony whereofI afli-x my signature in other shaped as a cone with grooves thereon, the presence of two witnesses.

and carrying a rotatable guide havingaseries HAROLD ROBINSON WELLMAN. of faces with grooves differently disposed on Witnesses:

said faces, and means for rotating said sheave, l. WERTHEIMER,

whereby the rope passing over said sheave J. B. OOWEN. 

